Adjuster and a packaging machine comprising said adjuster

ABSTRACT

A sealed adjuster ( 24 ) has a first portion ( 34 ) fixed to a first structure, a second portion ( 36 ) fixed to a second structure ( 30 ), and a manually operable third portion ( 38 ) adjustable to change the position of the first portion ( 34 ) relative to the second portion ( 36 ) such that, as the position of the first portion ( 34 ) is changed relative to the second portion ( 36 ), the position of the first structure is changed relative to the position of the second structure ( 30 ). The adjuster ( 24 ) also has a sealing arrangement ( 88, 90, 92, 96  and  116 ) for providing sealing among the first portion ( 34 ), the second portion ( 36 ), and the third portion ( 38 ).

The present invention relates to an adjuster and to a packaging machine.The adjuster may be for helping to position a top sealing mechanism fora container, but may instead be used for positioning other devices inthe packaging machine as well. The invention is applicable to packagingmachines and adjusters and positioning mechanisms of various differingconstructions and modes of operation.

In a form-fill-seal packaging machine, flat container sleeves to beturned into gable-top cartons are opened and are positioned asopen-ended sleeves on a multi-armed mandrel. The bottom of the containeris closed and sealed. The container is then stripped from the mandrelinto a horizontal endless chain conveyor when it reaches a rotary indexposition adjacent the conveyor. The container passes to a toppre-breaker station, and if the form-fill-seal packaging machine is alsoan aseptic machine, then on into a fogging station where a sterilizingagent is sprayed onto the inside surface of the container.

A drying station removes residual sterilizing agent from the container.The container then continues through the machine into a filling stationwhere the container is filled. The container is passed on to a topclosing unit where top closing panels are folded inwards, and thence toa top sealing station.

In the top sealing operation, a filled carton, with an open top end, isindexed into the top sealing station. The top flaps of the carton arefolded inward to form a gable shaped top, and the two fins are sealed toeach other, with heat and/or adhesive, thereby to seal the carton. Thisoperation is typically performed by what is often referred to as a topsealing mechanism having one or more fixed or movable jaws that engageand manipulate the top flaps to seal the carton as described.

During the various operations of the packaging machine, the variousmechanical devices used in the machine should be aligned properly withthe cartons being moved from one station to the next as the variousoperations are performed. Misalignment can occur in variouscircumstances—for example, chain stretch of the conveyor chain, skewingof the carton carriers, or during initial setup of the machine.Therefore, it is desirable that the various devices used in thepackaging machine be adjustable to accommodate various positions and/ororientations of the series of cartons moving through the machine. Forexample, the top sealing mechanism should be properly aligned with thecartons as the cartons are moved to the top sealing station. Alignmentbetween the top sealing mechanism and the cartons is more feasible ifthe top sealing mechanism is adjustable.

To this end, it is known to provide a positioning mechanism forcorrectly positioning any unit located along the conveyor chain, such asthe top sealing mechanism. The positioning mechanism includes severaladjusters that include threaded adjusting screws. Upon rotation of oneor more of the adjusting screws, the top sealing mechanism, or a portionthereof, is movable in a direction parallel to, or perpendicular to, oroblique to, the path of movement of the containers through the topsealing station. The adjusters include a plurality of fixed and movingparts, made typically from stainless steel. If the machine has a c.i.p.(clean-in-place) system, the cleaning fluid may tend to cause seizing-upof screw actions of the stainless steel adjusters, which can becounteracted by an anti-seizing compound. Furthermore, micro-organisms,such as bacteria, which have penetrated into interfaces of the adjustersare difficult for the cleaning fluid to access.

The adjusters typically have various moving parts, and must provide theability to adjust the position of a mechanism, e.g. a top sealingmechanism, without affecting the cleanliness of particularly an internalenvironment of the packaging machine, namely a machine having a clean,ultra clean, or aseptic environment. For the purposes of this patentapplication, “clean”, “ultra-clean” and “aseptic” internal environmentshave the following meanings which are based upon shelf lives of productssuch as milk and fruit juice and which we believe to be generallyunderstood within the liquid food packaging industry:

“clean” means a shelf life of up to two weeks in the cold chain. Partsof the packaging machine such as filler nozzles and top sealingmechanism can be unprotected, although they are often in a protectivechamber, more for safety reasons than for hygiene.

“ultra-clean” means a shelf life of up to three to six weeks in the coldchain. Parts such as filler nozzles and top sealing mechanism are in aprotective chamber for hygiene reasons. The levels of decontamination ofthe containers before filling and of sterility of air fed to theprotective chamber are relatively low.

“aseptic” means a shelf life of up to one year in ambient temperature.Again, parts such as filler nozzles and top sealing mechanism are in aprotective chamber for hygiene reasons. The levels of decontamination ofthe containers before filling and of sterility of air fed to theprotective chamber are very high.

It is therefore desirable to provide an adjuster which will not inhibitthe cleanliness of the machine in which it is used.

According to one aspect of the present invention, there is provided anadjuster, comprising:

a first portion arranged to be fastened to a first structure;

a second portion arranged to be fastened to a second structure;

a third portion connected to the first and second portions and manuallyadjustable to change the position of said first portion relative to saidsecond portion such that, as the position of said first portion ischanged relative to said second portion, the position of said firststructure is changed relative to the position of said second structure;and

a sealing arrangement providing a sealing function among said firstportion, said second portion, and said third portion.

According to another aspect of the present invention, there is provideda form-fill-seal packaging machine of a desired level of hygiene whichis at least clean, a mechanism for use in relation to a container, and apositioning assembly for said mechanism, said assembly comprising anadjuster which serves to adjust the position of said mechanism in apredetermined sense and which comprises:—

a first portion arranged to be fastened to a first structure;

a second portion arranged to be fastened to a second structure;

a third portion connected to the first and second portions andadjustable to change the position of said first portion relative to saidsecond portion such that, as the position of said first portion ischanged relative to said second portion, the position of said firststructure is changed relative to the position of said second structure;and

a sealing arrangement providing a sealing function among said firstportion, said second portion, and said third portion.

Owing to the invention, it is possible to provide an adjuster whereinthe risk of leakage of flowable substance outwards and/or penetrationinwards by micro-organisms is minimised.

In order that the invention may be clearly and completely disclosed,reference will now be made, by way of example, to the accompanyingdrawings, wherein:

FIG. 1 is a schematic view of a top sealing mechanism for a packagingmachine which includes a sealed adjuster;

FIG. 2 is a cut-away side elevation taken along the line 2-2 of FIG. 1of the top sealing mechanism;

FIG. 3 is a rear elevation of the top sealing mechanism;

FIG. 4 is a vertical axial section through one of a number of adjustersused in the sealed adjuster;

FIG. 5 is a partially exploded perspective view of the adjuster of FIG.4;

FIG. 6 is an exploded axial sectional elevation of the adjuster of FIG.4;

FIG. 7 is an enlarged axial sectional view of seals among a collar, anadjusting screw and a block of the adjuster of FIG. 4;

FIG. 8 is an enlarged axial sectional view of a sealing device between abase and a third portion of the adjuster of FIG. 4; and

FIG. 9 is a side elevation of a form-fill-seal packaging machineincluding a top sealing station incorporating the top sealing mechanism.

Referring to the drawings, a top sealing station is shown generally at10, having sealed adjusters 12 similar to each other for changing theposition of the top sealing station 10. The top sealing station 10 isused for top-sealing of a container 16. The container 16 is a gable-topcarton, which is commonly used for storing consumable fluids, such asjuice or milk. The station 10 is in a protected atmosphere chamber of aclean, ultra-clean, or aseptic, form-fill-seal packaging machine.

The top sealing station 10 includes a top sealing mechanism, generallyshown at 18, for sealing together the top closure sealing sub-panels 20of top closure panels 14 of the container 16. This top sealing mechanism18 may be of a known type. It is desirable that the position of the topsealing mechanism 18 be adjustable to ensure that the top sealingprocess is correctly carried out—that the sealing sub-panels 20 of thecontainer 16 are properly aligned, for example, when sealed to eachother.

To this end, at least a portion of the top sealing station 10 issupported on a positioning assembly 22 that includes at least oneadjuster 12. In this embodiment, however, there are three adjusters 12,a first adjuster 24, a second adjuster 26, and a third adjuster 28. Thepositioning assembly 22 is supported on a machine structure, which maybe a part of the frame or another structure of the machine 102 shown inFIG. 9. In this embodiment, the positioning assembly 22 is locatedbehind a panel 104 of the machine 102. The first sealed adjuster 24, thefunction of which will be described later, is secured to the machinestructure. The containers 16 are indexed along the machine structureinto a position at the top sealing mechanism 18, where the top sealingprocess is completed.

The positioning assembly 22 includes generally a first structure or base30 and a second structure or slider 32. The base 30 is movably connectedto the machine structure through the first sealed adjuster 24. Theslider 32 is supported on the base 30 for sliding movement relative tothe base 30. The slider 32 also supports other components of the topsealing station 10 as shown in FIGS. 1 to 3, including the top sealingmechanism 18.

In adjustment of the positioning assembly 22, as described below, theslider 32 is movable in one of two directions along the base 30, in aplane parallel to the base 30. The base 30 is also movable in one of twodirections along the machine structure, in a plane parallel to themachine structure. Additionally, the direction in which the slider 32moves relative to the base 30 is perpendicular to the direction in whichthe base 30 moves relative to the machine structure. This allows theslider 32 to be moved in any direction in a horizontal plane relative tothe machine structure. As a result, the top sealing mechanism 18 thatthe slider 32 supports is also movable in any direction in the plane inrelation to the machine structure.

The second and third adjusters 26,28 are similar or identical to eachother, and are substantially similar to the first adjuster 24. Eachadjuster 24,26 or 28 includes a first portion 34, a second portion 36,and a third portion 38 that is adjustable to set the position of thefirst portion 34 relative to the second portion 36. The first adjuster24 is used to set the position of the base 30 relative to the machinestructure, and the second and third adjusters 26 and 28 are used to setthe position of the slider 32 relative to the base 30.

The second portions 36 of all three adjusters 24,26 and 28 are identicalto each other, as are the third portions 38. However, the first portion34 of the first adjuster 34 is different from the first portion 34 ofthe second and third adjusters 26 and 28. Each adjuster 24,26 or 28includes a block 40; however, the block 40 of the first portion 34 ofthe first adjuster 24 is fixed to the machine structure by two bolts 42which extend through apertures 44 which are formed through two outersupport portions 46. The remaining parts of the first portion 34 andother components of the first adjuster 24 are identical to thecomponents of the second and third adjusters 26 and 28.

Each block 40 has a tubular portion 48 with a central bore 50. Thetubular portion 48 of the first adjuster 24 extends towards the base 30,and the tubular portions 48 of the second and third adjusters 26 and 28extend towards the slider 32. Separated from the bore 50 by an internalwall 52 of the block 40 is a small chamber 54 of the block 40. The wall52 forms a shoulder 56 at the inner end of the chamber 54. The outer endof the chamber 54 is open in a direction facing away from the slider 32.

The second portion 36 of each of the adjusters 12 includes a sleeve 58.As shown in FIG. 4, the sleeve 58 of the first adjuster 24 is fixed tothe base 30 by a bolt 60 received in a chambered end portion 62 of thesleeve 58. The base 30 has a corresponding shouldered aperture 64, andthe bolt 60 is a shoulder bolt 60 which extends into the correspondingshouldered aperture 64. Additionally, the sleeve 58 of each of thesecond and third adjusters 26 and 28 is fixed to the slider 32 by thesame type of bolt 60 which extends through a shouldered aperture(similar to the shoulder aperture 64) formed as part of the slider 32. Atubular portion 66 of the sleeve 58 extends from the end portion 62 in adirection toward the block 40. The tubular portion 66 includes internalscrew-threading 68. The outer diameter 70 of the tubular portion 66 isselected so that it can fit within the bore 50 of the tubular extension48 of the block 40.

The third portion 38 of each adjuster 12 includes an adjusting screw 72.The adjusting screw 72 is received in and supported on the block 40. Theadjusting screw 72 has a radially enlarged flange 74 that is received inthe chamber 54 of the block 40, with two washers 76. A collar 78, heldto the block 40 by four bolts 80, retains the flange 74 of the adjustingscrew 72 in the chamber 54. The adjusting screw 72 is thus supported onthe block 40 for rotation relative to the block 40, but is preventedfrom axial movement relative to the block 40.

The adjusting screw 72 has an externally threaded end portion 82extending toward the slider 32 (or the base 30, depending on where theadjuster 24,26 or 28 is used), within the bore 50 of the tubular portion48 of the block 40. The end portion 82 of the adjusting screw 72 isreceived in the internally threaded portion 68 of the sleeve 58. As aresult, rotation of the adjusting screw 72 causes relative axialmovement between the adjusting screw 72 and the sleeve 58. In the caseof the first adjuster 24, because the adjusting screw 72 is axiallyfixed to the machine structure and the sleeve 58 is axially fixed to thebase 30, rotation of the adjusting screw 72 causes relative axialmovement between the machine structure and the base 30. An anti-seizecompound is applied to the external screw-threading of the end portion82. It might also be applied to the flange 74 and the washers 76. Withregard to the second and third adjusters 26 and 28, rotation of theadjusting screws 72 causes relative axial movement between the base 30and the slider 32 because the adjusting screws 72 are axially fixed tothe base 30, and the sleeve 58 is fixed to the slider 32.

In the specific positioning assembly 22 illustrated in the drawings, thethree adjusters 24,26 and 28 are operable separately or together toprovide planar movement of the slider 32 along the plane of the base 30,and the base 30 along the machine structure. Adjustment of the firstadjuster 24 moves the base 30 in a direction shown by arrow 84.Adjustment of the second and third adjusters 26 and 28 moves the slider32 in a direction shown by arrow 86. Adjustment of only one of thesecond and third adjusters 26 and 28 on either side can produce pivotingmovement of the slider 32 on the base 30. As a result, the threeadjusters 24,26 and 28 are operable separately or together to provideplanar movement of the slider 32 over the plane of the base 30, and thebase 30 along the plane of the machine structure.

A plurality of seals is provided on each adjuster 24,26,28. The sealshelp to prevent air and foreign matter from entering into internalchambers and passages of the adjuster 24,26 or 28. Also, the seals helpto prevent dirt from accumulating at the joints between the moving partsof the adjuster 24,26 or 28. As a result, the seals help to keep theadjuster 24,26 or 28 clean, as is desirable in a clean, ultra-clean, oraseptic environment. Further, the top sealing station 10 is typicallyused in a machine 102 having a clean, ultra-clean, or asepticenvironment, as shown in FIG. 9. However, the top sealing station 10 mayalso be used as part of a machine having less than a clean environment.The seals provide the ability to clean the adjusters 24,26 and 28 bywashing, for example, with a c.i.p. internal spray system of the machine102 without sprayed fluid getting inside the adjusters 24,26 and 28.

The seals of each adjuster 24,26 or 28 include a first seal 88, which inthis embodiment is a wiper seal 88, mounted on the collar 78 and sealingthe moving joint between the collar 78 and the shaft of the adjustingscrew 72, closing the open end of the chamber 54. The wiper seal 88serves to deter egress into the protective chamber of any anti-seizecompound applied to the flange 74 and the washers 76 and to deteringress from the chamber of micro-organisms to between the collar 78 andthe shaft of the screw 72.

The seals of each adjuster 24,26 or 28 include a second seal 90, whichis also a wiper seal, mounted on the tubular portion 48 of the block 40,and sealing the moving joint between the block 40 and the sleeve 58,closing the open end of the tubular portion 48 and receiving the sleeve58. The second seal 90 serves to deter egress into the protectivechamber of anti-seize compound applied to the screw-threading of thescrew 72 and to deter ingress from the chamber of micro-organisms tobetween the tubular portions 48 and 66.

The seals of each adjuster 24,26 or 28 include a third seal 92, which isan O-ring seal, mounted on the collar 78 and sealing the fixed jointbetween the collar 78 and the block 40. The seal 92 serves to deteringress from the protective chamber of micro-organisms to the chamber 54via the interface between the block 34 and the collar 78.

The seals on each adjuster 24,26 or 28 include two additional O-ringseals 94 which are part of a sealing device 96. The device 96 alsoincludes a spacer 98 which has circumferential grooves 100 for receivingthe O-ring seals 94. Each groove 100 has a lip 102 which helps to retainthe seals 94 in the grooves 100. The device 96 is interposed between thebase 30 and the end portion 62, to deter accumulation of foreign matter,as well as ingress of micro-organisms, at the fixed joint between thosetwo parts. When the bolt 60 is tightened, the end portion 62 and thebase 30 (or slider 32, depending on which adjuster 24,26 or 28 is beingused) will be pressed against the spacer 98, compressing the O-ringseals 94 in the grooves 100. This will cause the O-ring seals 94 todeform, and bulge out of the grooves 100. This will reduce theprobability of foreign matter settling in the grooves 100, eitherbetween the O-ring seals 94 and the lips 102, between the O-ring seals94 and the end portion 62, or between the O-ring seals 94 and the slider32 (or base 30 when referring to the first adjuster 24).

The structure and mounting of the O-ring 92 are shown in more detail inFIG. 7. The O-ring 92 is captured initially in a groove 104 in thecollar 78. The collar 78 has an outer lip 106 that projects part-waytoward the mating surface of the block 40 and that helps to retain theO-ring 92 in the groove 104.

When the collar 78 is clamped down tight against the block 40, lip 106does not engage the mating surface. The dimensions of the O-ring 92 areselected so that a portion of the O-ring 92 bulges out of the groove 104in the space between the lip 106 and the mating surface. Again, thepossibility of foreign matter, for example micro-organisms, migratinginto the groove and being retained there, either between the O-ring 92and the lip 106, or between the O-ring 92 and the mating surface, islessened. Therefore, each adjuster 24,26 or 28 is maintained in acleaner state.

The sealing device 96 is used not only between the slider 32 and eachsleeve 58 of the adjusters 26 and 28 but also between other parts of theadjusters 24,26 and 28 as well. Two sealing devices 96 are used betweenthe first adjuster 24 and the machine structure, as shown in FIGS. 1 to5. The bolts 42 extend through the sealing devices 96, and the devices96 are located between the outer support portions 46 and the machinestructure.

There are two more sealing devices 96 used between the second and thirdadjusters 26 and 28 and the base 30. The second and third adjusters 26and 28 also have bolts (not shown), similar to the bolts 60, whichextend through the bottom of the base 30 and through the sealing devices96 up into the blocks 40 of the second and third adjusters 26 and 28.The second and third adjusters 26 and 28 are thereby secured to the base30.

The positioning assembly 22 also includes a set of positioning bolts110. The positioning bolts 110 extend through the base 30, and canoptionally each have a washer 112. The positioning bolts 110 arereceived into corresponding slots (not shown) in the machine structureand guide the movement of the base 30 along the machine structure.

There are also additional washers 114 and 116 which can be used for thebolts 42 and the bolts 80. These washers may be in the form of seals todeter ingress of micro-organisms to between the bolts 42 and the topsurfaces of the portions 46 and to between the collar 78 and the bolts80.

1-31. (canceled)
 32. An adjuster, comprising: a first portion arrangedto be fastened to a first structure; a second portion arranged to befastened to a second structure; a third portion connected to the firstand second portions and manually adjustable to change the position ofsaid first portion relative to said second portion such that, as theposition of said first portion is changed relative to said secondportion, the position of said first structure is changed relative to theposition of said second structure; and a sealing arrangement providing asealing function among said first portion, said second portion, and saidthird portion.
 33. An adjuster according to claim 32, wherein said firstportion further comprises: a block arranged to be fastened to said firststructure; a tubular portion of said block, said tubular portion beingarranged to extend toward said second structure; a central bore of saidtubular portion; a chamber bounded by said block; an internal wallformed as part of said block, said wall separating said bore from saidchamber; and a collar connected to said block to bound said chamber,part of said third portion extending through said collar and saidchamber into said central bore, said sealing arrangement providing asealing function between said collar and said third portion and alsoproviding a sealing function between said collar and said block.
 34. Anadjuster according to claim 33, wherein said sealing function betweensaid collar and said third portion is provided by a wiper seal.
 35. Anadjuster according to 33, and further comprising: at least one outersupport portion; an aperture formed in the or each outer supportportion; and a fastener for extending through said first structure intothe or each aperture in order to secure said block to said firststructure.
 36. An adjuster according to 33, wherein said second portioncomprises: a sleeve; an end portion of said sleeve arranged to bemounted on said second structure such that said sleeve is pivotable inrelation to said second structure, a sealing device of said sealingarrangement being arranged to be disposed between said end portion andsaid second structure; and a tubular portion of said sleeve extendingtoward said first portion, and a seal circumscribing said tubularportion of said sleeve and being disposed between said tubular portionof said sleeve and said first portion.
 37. An adjuster according toclaim 36, wherein said tubular portion of said sleeve extends into saidtubular portion of said block.
 38. An adjuster according to claim 32,wherein said third portion comprises a manually rotatable adjustingscrew supported by said first portion and having a threaded portionreceived in said second portion.
 39. An adjuster according to claim 38,wherein said third portion further comprises a radially enlarged flangeof said adjusting screw serving to deter axial movement of said screw.40. In combination, an adjuster according to claim 32, a baseconstituting said first structure and a slider constituting said secondstructure.
 41. A combination according to claim 40, wherein said slideris part of a top sealing station positioned upon said base.
 42. In aform-fill-seal packaging machine of a desired level of hygiene which isat least clean, a mechanism for use in relation to a container, and apositioning assembly for said mechanism, said assembly comprising anadjuster which serves to adjust the position of said mechanism in apredetermined sense and which comprises:— a first portion arranged to befastened to a first structure; a second portion arranged to be fastenedto a second structure; a third portion connected to the first and secondportions and adjustable to change the position of said first portionrelative to said second portion such that, as the position of said firstportion is changed relative to said second portion, the position of saidfirst structure is changed relative to the position of said secondstructure; and a sealing arrangement providing a sealing function amongsaid first portion, said second portion, and said third portion.
 43. Amechanism as claimed in claim 42, wherein said assembly comprises asecond adjuster which serves to adjust the position of said mechanism ina second sense different from the first-mentioned sense.
 44. A mechanismas claimed in claim 43, wherein, for the or each adjuster, said firstportion further comprises: a block; a tubular portion of said block,said tubular portion being arranged to extend toward said secondportion; a central bore of said tubular portion; a chamber bounded bysaid block; an internal wall formed as part of said block, said wallseparating said bore from said chamber; and a collar connected to saidblock to bound said chamber, part of said third portion extendingthrough said collar and said chamber into said central bore, saidsealing arrangement providing a sealing function between said collar andsaid third portion and also providing a sealing function between saidcollar and said block.
 45. A mechanism as claimed in claim 44 andfurther comprising, for the or each adjuster: at least one outer supportportion; an aperture formed in the or each outer support portion; and afastener for extending through said first structure into the or eachaperture in order to secure said block.
 46. A mechanism as claimed inclaim 44, wherein, for the or each adjuster, said second portioncomprises: a sleeve; an end portion of said sleeve arranged to befastened such that said sleeve is pivotable, a sealing device of saidsealing arrangement being adjacent said end portion; and a tubularportion of said sleeve extending toward said first portion, and a sealcircumscribing said tubular portion of said sleeve and being disposedbetween said tubular portion of said sleeve and said first portion. 47.A mechanism as claimed in claim 46, wherein, for the or each adjuster,said tubular portion of said sleeve extends into said tubular portion ofsaid block.
 48. A mechanism as claimed in claim 43, wherein, for the oreach adjuster, said third portion comprises an adjusting screw supportedby said first portion and having a threaded portion received in saidsecond portion.
 49. A mechanism as claimed in claim 48, wherein, for theor each adjuster, said third portion further comprises a radiallyenlarged flange of said adjusting screw serving to deter axial movementof said screw.
 50. A mechanism as claimed in claim 42, wherein saidmachine includes a base constituting said first structure and a sliderconstituting said second structure.
 51. A mechanism as claimed in claim50, wherein said slider is part of a top sealing station positioned uponsaid base.